Hi Have bought one of the Max Pro FM exciters, 15W, and proven my design, but I now need a FM transmitter with a couple hundred milliwatts power, I only want a range of 30m-50m. I still need to use the RDS data stream though

Is there any way I can modify my Max Pro 15W to only put out (say) 150mW? Is there another tranmitter I could buy?

Also, the antenna now needs to be very small. How do I design an antenna for 87.5MHz at 150mW that is really small?